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41.
K. Nakanishi T. Masukawa T. Nadai K. Yoshii S. Okada K. Miyajima 《Journal of inclusion phenomena and macrocyclic chemistry》1996,25(1-3):181-184
Triacetyl--cyclodextrin (TA--CyD), a hydrophobic cyclodextrin derivative, that is insoluble in water, was used to form a complex with flufenamic acid (FA). FA-TA--CyD complex formation was demonstrated by differential scanning calorimetry and powder X-ray diffractometry. The release rate of FA from the FA-TA--CyD complexes in phosphate buffer pH 6.8 was significantly retarded compared to that of FA from the FA and glucose mixture. When the FA-TA--CyD complexes were administered directly into the intraduodenal lumen, the plasma concentration of FA remained at a plateau level (10-18 g/ml) for 6–8 h. An increased mean residence time of FA following FA-TA--CyD complexes administration was observed. These results indicate that TA--CyD may serve as a hydrophobic carrier in prolonged-release preparations of FA. 相似文献
42.
43.
Soichi Okada 《Journal of Algebraic Combinatorics》1993,2(2):155-176
An alternating sign matrix is a square matrix whose entries are 1, 0, or –1, and which satisfies certain conditions. Permutation matrices are alternating sign matrices. In this paper, we use the (generalized) Littlewood's formulas to expand the products
and
2 as sums indexed by sets of alternating sign matrices invariant under a 180° rotation. If we put t = 1, these expansion formulas reduce to the Weyl's denominator formulas for the root systems of type B
n and C
n. A similar deformation of the denominator formula for type D
n is also given. 相似文献
44.
N-[2-(D-Glucos-3-O-yl)propionyl]-L-alanine ( 7a ) was synthesized, which has a glucose residue instead of N-acetylglucosamine residue in the muramyl peptide. N-[(D-Glucos-3-O-yl)acetyl]-L-alanine ( 7b ) was also synthesized as a glycolyl analog of 7a in order to determine the relationship between the structure of propionyl moiety in the carbohydrate analog ( 7a ) and the adjuvant activity. These simple analogs are compounds prepared for the purpose of introduction into a synthetic polymer with the view of producing polymeric drugs. 相似文献
45.
Neil C. Concibido Tetsuji Okuda Wataru Nishijima Mitsumasa Okada 《Reaction Kinetics and Catalysis Letters》2006,89(2):369-376
Summary The hydrodechlorination of tetrachloroethylene in methanol (MeOH) over palladium catalysts on activated carbon (Pd/C) at 20°C
and atmospheric pressure was rendered safer by using ethanol (EtOH), isopropanol (IPA) or water-alcohol mixtures as solvents.
Adding water to MeOH was better than using EtOH or IPA since it resulted in a faster reaction and better stability of Pd/C,
which could also be completely reactivated. 相似文献
46.
47.
48.
Takuma Shinya Nakashima Noriyuki Tantirungkij Manee Kinoshita Shinichi Okada Hirosuke Sew TatsÜji Yoshida Toshiomi 《Applied biochemistry and biotechnology》1991,28(1):327-340
Applied Biochemistry and Biotechnology - A NADPH/NADH-dependent xylose reductase gene was isolated from the xylose-assimilating yeast,Pichia stipitis. DNA sequence analysis showed that the gene... 相似文献
49.
Recently, high-performance nano-scale flow pumping systems have been developed for micro and miniaturized analysis systems. A novel device capable of measuring and monitoring nanoliter scale flow rates has been required for the further development of the pumping system. In this study, an atomic emission detector using helium radio-frequency plasma (RFP-AED) was used for the measurement of the nanoliter scale flow rate of water by quantitatively detecting the emission from hydrogen in the water molecules. Monitoring nano-flow rates of water in the range up to 1.0 microl min(-1), and the change in the flow rate by the indication of the ratio of the emissions of H (656.3 nm) and He (667.8 nm) were successful. At present, the lowest flow rate that could be determined reproducibly was 4 nl min(-1) calculated as five times the standard deviation of the background noise. Additionally, similar evaluations for the deviation of each flow rate by using the RFP-AED and a flow-injection system were produced. 相似文献
50.
In the course of a population study of alpha 1-antitrypsin polymorphism by separator isoelectric focusing, a variant phenotype having a somewhat narrower spacing than PI M1M3 was observed in a Japanese blood donor. Family studies by hybrid isoelectric focusing in a carrier ampholyte-supplemented immobilized pH gradient from 4.35-4.65 revealed that the products of the responsible gene, PI*Mtoyoura, were extremely close but slightly cathodal to those of PI*M1. The difference in isoelectric point between them corresponded to the resolving limit of isoelectric focusing. For this reason, although the propositus' father was deduced to have the genotype PI*M1/PI*Mtoyoura, the products of these two genes failed to form a double band pattern. Thus, the gene frequency for PI*Mtoyoura was unknown. These findings, however, indicate that a further microheterogeneity in the PI M subtype exists at least in the Japanese. 相似文献